1. Field of Invention
This invention relates to systems and methods for cleaning oxygen lines.
2. Description of Related Art
Oxygen lines are used in many applications, such as in aircraft, submarines, medical facilities and the like. These oxygen lines must be clean, since they carry oxygen that will be breathed by humans. If the lines become contaminated for any reason, they must be cleaned prior to further use.
Currently, oxygen lines are taken to a cleaning laboratory, such as the Naval Oxygen Cleaning Laboratory located at Indian Head, Maryland, for cleaning. A large, freon-based cleaning system is set up at these laboratories, which is set up in a building and not easily moved. For example, this system includes large tanks used for cleaning medium recovery procedures. For safety reasons, these tanks are located outside of the building and accessed by pipes leading from the inside of the building to the outside of the building. The system also requires clean rooms, which are located in the building. Additionally, distilling equipment for handling the freon is required as part of the system, and this distilling equipment is bulky and includes vapor recovery vents and the like.
Moreover, there are relatively few such laboratories, and due to backlogs, the entire cleaning process can take from several days to more than a month. Moreover, since these laboratories are operated by the military, oxygen line cleaning jobs for the military are often given priority over civilian jobs. Thus it is inconvenient and time consuming to have oxygen lines cleaned in such a manner.
Furthermore, the system used by these laboratories passes freon-based cleaner through the oxygen lines to clean them. It is attempted to re-use the freon by boiling the freon to remove contaminants. However, much of the freon is lost during the boiling process, which results in a relatively large amount of freon waste each time a line is cleaned. For example, to clean a single oxygen line, 10 gallons of freon are typically used, but only about 3 gallons of reusable freon are recovered. Moreover, freon is considered to not be an environmentally friendly substance, and disposal of the contaminated freon is problematic.
Others have attempted to invent a non-freon-based, portable system, but have failed.
The inventor has discovered how to make a more accessible, economical and environmentally friendly oxygen line cleaning device. An oxygen line cleaning device according to this invention uses a silicated alkaline cleaner, such as Oxygen Cleaning Compound (OCC), manufactured by Octagon Process Inc. in Edgewater, N.J. The cleaner is passed through an oxygen line, and may then be filtered to remove contaminants and recirculated through the oxygen line or otherwise reused.
OCC is considered to be an environmentally friendly product, and thus disposal and handling is much easier than with the conventional freon-based cleaner. The Navy currently uses OCC (a.k.a. NOC) as a parts cleaner because it is safe and stable and may be taken aboard submarines and the like. However, the Navy has not used OCC to clean oxygen lines.
The inventor has discovered that, by cleaning oxygen lines with OCC, oxygen lines can be cleaned to a purity of about 98% or more. The above-described conventional process only achieves a purity of about 87%-93%.
Additionally, in contrast to the conventional system which requires large, expensive equipment typically available only in a specialized cleaning laboratory, this invention may be implemented in a compact, portable, relatively inexpensive device that is easily transported to a location convenient to a user.